Researchers have been trying for more than 70 years to develop a vaccine against the elusive malaria parasite without notable success. Two studies conducted in East Africa suggest that they are finally closing in on their goal.

The Bill and Melinda Gates Foundation deserves huge credit for enabling this research to go forward when the drug manufacturer was unwilling, on its own, to take the financial risk to try to develop a vaccine.

The new studies showed that the most advanced candidate vaccine - made by GlaxoSmithKline - cut illnesses in infants and young children by more than half and could safely be given with other childhood vaccines that are already routinely administered throughout Africa.

There is no guarantee of success. The studies were carried out in areas with relatively low transmission of malaria; no one knows if the vaccine will work as well where malaria is more rampant.

Even a vaccine that is partially effective could save hundreds of thousands of lives a year. It would bolster the gains already being made by insecticidetreated bed nets that prevent mosquitoes from spreading the parasite and by malaria pills to treat sick patients.

That the candidate vaccine has gotten this far is a tribute to the power of charitable contributions to generate and sustain industrial interest.

Glaxo had been funding development of a vaccine aimed at military personnel and travelers but was unwilling to undertake pediatric studies unless a financial partner could be found. That’s when the Gates Foundation came to the rescue. It has pumped in $107.6 million so far. Glaxo says it has spent about $300 million and expects to invest $50 million to $100 million more to complete the project. If all goes well, the vaccine could be submitted for regulatory approval in 2011.